Home » Blog » Outlook Tips » Fix Synchronization Issue While Synchronizing Your Exchange Server .OST File in Outlook

Fix Synchronization Issue While Synchronizing Your Exchange Server .OST File in Outlook

Published By Nilesh Kumar
Debasish Pramanik
Approved By Debasish Pramanik
Published On January 16th, 2024
Reading Time 6 Minutes Reading
Category Outlook Tips

OST or Offline Storage table file is created with .ost as file extension always whenever Microsoft Exchange mailbox is configured in MS Outlook. With the help of this OST file, one can easily access exchanged emails in an offline mode also. So, whenever the connection is established again with Exchange Server, it can also be possible that the server is not able to sync all emails in OST file that can further lead to problems while sending and receiving emails. All these creates a synchronization problem when a user synchronizes the Exchange Server .ost file in Outlook. Thus, in this post, different approaches to troubleshooting the OST file synchronization issue are discussed.

Solution to Troubleshoot Outlook Synchronization Issue

There are various troubleshooting ways to resolve the problem that a user might encounter while synchronizing an Exchange Server mailbox with a .ost file of Outlook.

Verify Offline Folder is Synchronized Properly or Not

To make sure that offline folders are synchronized correctly, follow the steps listed below:

1. First of all, right-click on the folder for which you want to confirm and then, click on the Properties option
2. Next step is, go to Synchronization tab.
3. After that, you need to navigate to the Statistics of this folder and verify the settings in the following fields:

Last Synchronized on: Date
Offline folder contains: number of Items
Server folder contains: number of Items

To check the synchronization, match the number of items in server folder and offline folder, if both have same value then, synchronization is working properly. Otherwise, go to Profile settings. To do the same, follow the steps below:

For Microsoft Outlook 2003

1. To begin, click on Tools >> E-mail Accounts option
2. After that, in E-mail Accounts dialog box, make sure that View or change existing e-mail accounts option is checked, and then click on the Next to continue
3. Then, check in the Deliver new mail to the following location menu, Mailbox-account name is checked
4. Now, click on the Microsoft Exchange Server and then, on Change option
5. Next, Select the Use Cached Exchange Mode option >> Next
6. Finally, click on Finish >> OK button
7. Then, exit MS Outlook and open it again

For MS Outlook 2007

1. To start, navigate to the Tools >> Account Settings option
2. After that, go to Data Files tab, and verify the default name is set as Mailbox- account name or not
3. Next, you can navigate to E-mail tab >> Mailbox- account name >> Settings option
4. Then, verify the Use Cached Exchange Mode option is selected or not from the Advanced tab, and then, click on the OK
5. Now, from the Account Settings dialog box, click on Close option
6. In last, exit the application and reopen it

For Microsoft Outlook 2010

1. Click on File >>Account Settings and again click on Account Settings option
2. Then, you need to click on the Data Files tab, and confirm that Mailbox- account name is set as default
3. After that, click the E-mail tab >> Mailbox-account name >> Change option
4. Then, check Use Cached Exchange Mode option is selected or not and then, click on OK to continue
5. Next, just click on Close button in the Account Settings option
6. Finally, come out of the MS Outlook and open it again.

Manually Synchronize OST folder with Exchange Server

When you are sure about synchronization settings, follow the steps given below:

1. First of all, you need to open Folder List pane and choose the folder that you wish to synchronize
Note: if there is no Folder List pane, then click on the Go menu >> Folder List option

2. Then, click on Tools >> Send/Receive >> This Folder (Microsoft Exchange Server) option in order to sync one offline folder only or click on Send/Receive All option to sync all offline folders

Automatically Synchronize OST File with Exchange Server

If you want to synchronize all offline folders automatically always, follow the steps given below:

1. To start, go to Tools >> Options >> Mail Setup option
2. After that, select the Send immediately when connected option from the Send/Receive section
3. Then, you need to click on Send/Receive option to open Send/Receive Groups dialog box
4. In last, make sure that the Perform an automatic send/receive when exiting option is marked or not, then click Close >> OK option

How to Create New OST File

If any of the above solutions does not work out, then create a new OST file and synchronize it again with Exchange Server.
1. Locate OST file in your system
2. Then, you need to rename the OST file extension (for example,.old).
3. After that, go to File >> Close option
4. Now, you need to start MS Outlook application
5. Go to Tools >> Send/receive >> Send/Receive All option

Try to Resolve Issue using OST Integrity Check Tool

One can also go for the OST Integrity Check tool (scanost.exe) in Outlook 2003 and Outlook 2007, which is an inbuilt utility that one can use only OST file. It scans the OST file eliminates all synchronization issues by restoring the lost information by comparing mailbox items or folders through the scan log that are maintained in the “Deleted Items” folder.

As it is an easy and convenient way to resolve the OST synchronization issue but there are some limitations like it does not fix major level corruption issues in OST file. Moreover, scanost.exe is not available in Microsoft Outlook 2010 and above. So, in that case, also it fails. Therefore, in order to have a foolproof effortless solution, one can go for a professional solution i.e. OST to Outlook PST Conversion. It is a one-stop solution to fix any type of issue in OST file without Outlook.

Final Words

OST file synchronization issues are commonly faced the problem by MS Exchange users. Therefore, we have discussed various solutions to fix synchronization problem when a user synchronize the Exchange Server .ost file in Outlook. However, there are various limitations that a user might face while using these methods. Thus, to prevent all such limitations one can go for OST Repair Tool, which can easily resolve all OST file issues in a just number of clicks.


By Nilesh Kumar

As a Chief Technical Writer, I know the technical issues faced by home and professional users. So, I decided to share all my knowledge via this blog. I love to help you with challenges while dealing with technical jargon.